Preparation of the Pathology Report for a Toxicology Study

Abstract The results presented in the pathology report are significant to the interpretation of a compound’s toxicity. Development of pathology data begins with understanding the protocol, followed by careful evaluation of the clinical pathology and post-mortem data. Documentation of findings must use formats that are predetermined and orderly. A peer review of the microscopic data provides a quality check. In the written report the post-mortem data should be distilled into a concise document that is readily understood and can be incorporated into the final study report. Because of the volume of post-mortem information and various formats used by contract laboratories, the pathologist must distill significant findings into text tables and use concise text to discuss compound, dose- and sex-related findings, and their significance. The report should integrate data from other sections of the study in order to achieve a thorough understanding of the pathophysiology of test-compound related effects, when possible. A poorly written report leaves questions in the reader(s) mind, may require hours of discussion to clarify, and could lead to a lengthened review time by regulatory agencies. The pathologist should keep in mind the information the client expects to find in the pathology report. This includes the target organs, their relationship to dose or exposure, their relationship to changes noted in other parameters assessed in the study, the reversibility of the findings once dosing stops, and the no observed adverse effect level (NOAEL).